A novel carbon thermal reduction approach to prepare recorded purity β-Ti3O5 compacts from titanium dioxide and phenolic resin

Abstract

Abstract β-phase titanium pentoxide (β-Ti3O5) has great potential applications in sensors, electrodes and laser devices, due to its unique phase-transforming behaviors. However, just this reversible phase transition behaviors between λ and β phases made its high purity preparation be challenging, and the high energy consumption of present industrialized method also limited the high-level applications of β-Ti3O5. In this work, a novel carbothermal reduction method has been acquired to produce highly pure β-Ti3O5 compacts from titanium dioxide “wrapped” by phenolic resin served as carbon source. Their phase and microstructure evolutions during the whole reaction process were systematically characterized under the assistance of Rietveld refinement and SEM images. The highly active pyrolytic carbon of phenolic resin could deposit on the surface of TiO2 and this compacted state could promote the generated CO to accelerate the reaction process and decrease the addition of reductant, simultaneously. The reduction sequences were TiO2→ Ti4O7→ Ti3O5→ Ti2O3. The weight ratio of phenolic to precursor of 9.0% could achieve the pure β-Ti3O5 as high as 98.06% under the calcination temperature of 1250\xa0°C for 4\xa0h. This work provided a novel and industrialized route to prepare β-Ti3O5 for applications in sensor and electrode in electrochemical reactions.